Yes.
I don't tell people what to do in their personal life. Because of my former profession, in a general sense, I do wish fewer smoked. It's not a good habit.
That being said, people are free to do whatever they want when they don't harm others. I do believe in self-determination. It's why I don't get on a soap box about any personal practices here.
My son smoked for awhile. Only thing I said to him about it was "You know I wish you wouldn't smoke, right?" He said he understood that I didn't like the practice. But that was that. I didn't make a big deal out of it. The more you tell your young adult children what to do, the more likely they'll continue to do it, in my experience.
He quit on his own and I can't take credit for it because we never spoke about it again.